You know what? Peony might just be the best supporting dancer now. At least for me.
Pure stats-wise, she can't hold a candle to LAzura with her +6 to all stats, and she doesn't give +1 movement to infantry and fliers, but Gentle Dream is the game changer here. A better version of Ground Orders as a free skill is excellent in practice. It opens up so much more positioning options for you. As an example, Peony, being a flier, can be positioned on forests, mountains, lava etc. and basically teleport units who would otherwise be inhibited by the terrain. Not just one, but multiple since you can chain them together. It's much easier to do than Ground Orders since it affects units in a line of Peony and the unit she dances as well.
The free +3 to atk/spd is icing on the cake. I think it's better than drive skills honestly. While it doesn't affect units diagonally of her, she can buff units from across the map, which can be vital for a frail dancer by staying away from the front, especially one that's weak to bows. Her Res and Spd are pretty good though and she can tank red mages like Aversa on a whim. To compare, Peony has 38/16/27 defenses with 36 spd. LAzura has 33/17/24 with 38 spd. Of course, if your team is heavily infantry or flier, then LAzura is probably better for the reach and pure stats she provides.